Tube sealing press



April 18, 1939. C. J WESTlN 2,155,029

1:11131: SEALING PRESS Filed July 2o, 1935 2 Sheng-sheet 1 April 18, 1939.

C. J. wEsTlN 2,155,029

TUBE SEALING PRESS Filed July 2o, 1935 2 sheets-sneer 2 l N V EN TOR.

ATTORNEY.

Patented Apr. i8, 1939 i UNITED sTATEs PATENT OFFICE TUBE SEALIN G PRESS Charles J. Westin, Philadelphia, Pa., assignor-to F. J. Stokes Machine Oompany, Philadelphia., Pa., a corporation of Pennsylvania Application July 20, 1935, Serial No. 32,383

8 Claim!- (Cl. 113-1) This invention pertains to a collapsible tube devices are eliminated and several important imsealing press and particularly to improvements provements incorporated so that a safe and dein presses used to emboss and seal containers pendable sealing device is produced. having clipless closures and/or clipless cement- The attached drawings illustrate a preferred .n sealed closures. construction of my improved sealing press: 5

The purposeof this invention is to provide Fig. 1 represents aview in perspective.

simple and conveniently adjustable but positive Fig. 2 represents a side elevation with parts means: broken away so as to show the double cam.

For applying the proper pressure to the closure; Fig. 3 is a section taken on line 3-3 of Fig. 2. l For setting the embossing or indenting punches Fig. 4 shows the cam assembly. l0 to the exact and safe depth of impression; and In its simplest form, the machine consists of For controlling the time the pressure and/or a housing or frame 23 within the walls of which heat and pressure are applied. the parts are mounted. A lever having one long Heretofore simple presses which were hand arm- 35 carrying the roller Il on pin I2 and av l5 or foot operated through levers and links have shorter arm 20 carrying the lower indenting 15 been used quite satisfactorily in sealing or crimppunches I9 is fulcrumed at 5I. Lever arm 20 ing the conventional clips into place around the extends out through an opening 22 in housing 23 folds of the closure. When clips were used, it and supports the lower indenting punch i9 in was not so important how the pressure was ap-v alignment with the upper indenting punch i1 plied as long as it was sufllcient to press the clip which is supported on the rigid part I6 of the 20 tightlyV around the foldsx If too much pressure housing 23. An extension i9 of lever 20 extends was applied, the stiffness of the clip tended to up in back of the lower indenting punch I3 so protect the softer metal in the folds and prevent as to form a stop for the collapsible tubes to be crushing of this, while if insuillcient pressure was acted on as they are placed between the punches.

2' applied this would be detected by the looseness Roller 4l bears against the double cam 36--33 26 of the clip; neither was the speed with which the which is fastened to the shaft 39. In this case a pressure was applied of any particular moment. spring 2l, supported by a lug 25 on housing 23,

In sealing the clipless closures, however, aca serves to .press the lever bearingvarm 35 and roller cording to the methods disclosed in U. S. Letters 4i against the cam surface.

Patent Nos. 1,989,031 and 1,989,032 granted to The double cam consists of a central eccentric 30 me on January 22, 1935, and No. 2,028,112, 33 keyed to shaft 39 and provided-with a flange granted to me on January 14, 1936, as well as in 45 which forms a guide for the adjustable outer my co-pending applications Serial Nos. 667,823; 'cam 36 on this side. On the other side the acl-I 667,824; and 696,145, it is very important to have justable cam 36 is guided by collar 44 fastened dependable control over every factor in the to inner eccentric 39. The outer cam 36 may 35 crimping and sealing operations. For example, also be an eccentric. By moving it in relationwhen flat sealing jaws are used and excessive ship to the inner eccentric 39 so that the zero pressure applied, the metal of the foldsis crushed mark of the graduations 31 is either on the left and cracks open at the creases of the folds; if or the right-hand side of the arrow, the stroke 40 excessive pressure is applied to indenting punches imparted by turning the cam assembly 180 or 40 or they are allowed to come too close together, 360, as the case may be, would, naturally be the metal in the folds will be punctured; and if varied in proportion to the distance the'outer the pressure is applied too suddenlylike a hamcam is moved away from the arrow. This cam mer blow-the metal between the indentations is may alSObe 0f irregular Outline but With an eX- not given a chance to flow naturally but is weaktended face of uniform distance from the center ened and may be ruptured by the sudden stretchof shaft 39 so as to keep the roller 4| pressed ing. In cement-sealedtubes, when heat is redown a. longer time and thus extend the time quired, the time element is of considerable imduring which the indenting jaws are held toportance. The heat must be transferred by congether. As is best seen in Fig. 2, movement of tactfrom the heated jaws into and through the cam 36 into the position shown in broken lines 50 folds in order to fuse or render this cement sufiiat l0 moves follower 4| and consequently shaft ciently plastic toform a perfect bo'nd between the 42 into the position shown in broken lines at 43. cement coated surfaces and this consumes ap- The effect of changing the relative position bepreciable time. tween the eccentric 39 and the outer cam 3,6 may Through this invention the defects of the old be seen to better advantage in Fig. 4, where cam u 36 is shown in position 52 having its major axis 53 coincident with the major axis of inner cam or eccentric 38. By moving the major axis 53 of outer cam 36 about 30 or to a position 54, the outer cam by this change takes the position 55. The resulting change in height of stroke produced by a revolution of the cam assembly might be assumed to beabout 1;/8 or as shown at 55. 'I'he lever 20, 35 is so fulcrumed that its proportions are one to four, the cam 36 acting on the longer arm 35. As suggested above, if the stroke is reduced 1/3 by changing the relative position of the cams, the effect of this change on the stroke of the short arm 20 would only be 'I'he above change of stroke was the result of changing the position of the major axis about 30. If the change of the relative position is only about 1, the effect on the relative closeness to which the jaws come would be only .001. This sensitiveness in adjustment of the closeness to which the jaws can be adjusted is very desirable because the wall thickness of collapsible tubes is only a few thousandths of an inch and, therefore, a change of a few thousandths if in the wrong direction, would be very destructive as far as the tightness of the closure is concerned.

When using presses of this type for sealing collapsible tubes treated with thermo-plastic cement, the heat for fusing the cement is trainsmitted to and through the folds by the direct contact of the tube folds with the ndenting punches. The tube must be kept in contact with the sealing punches sufficiently long to permit sufficient transfer of heat to raise the mass in the folds of the tubes to the same temperature as the ndenting punches. The temperature of the ndenting punches must be maintained at the fusing heat and this should completely permeate through the folds. If the temperature of the ndenting punches is increased above the fusing temperature of the cement, the outside will be burned and destroyed.

Heat may be supplied to the ndenting punches by the use of electric heaters. For the upper indenting punch l1 a heater i5 is placed in a chamber machined in the solid part i6 of housing 23. For the lower punch I9 heater 2l is placed in the chamber provided in the lever extension 20. The heater I5 is connected to switch l2 through cable 3l and heater 2| is connected to switch l2 through cable 33.

Some sort of heat control must be used and this may be either a rheostat, thermostat or a bi-metal type of control. In this case I have shown a thermostat with the bulb placed in a chamber at i4 and connected through a tube 32 to the thermostat at 28. Temperature variations are obtained by adjusting the knob 30. In some cases, it is desirable to have individual controls for each heater and a chamber 34 is, therefore, provided also in lever arm 35. The line current is connected to switch I2 at i3 and carried from the switch through 21 to the thermostat 28. For convenience in checking whether the current is on or not, a pilot lamp 26 is placed in a socket H which is connected in line with the switch. All the control devices may be mounted on a panel 29 which is supported on the housing in any convenient way. The cam shaft 39 may be operated either manually by a handle 41 or it may be connected to a prime-mover through couplings 46, 48, 46 being attached to the cam shaft 39 and the mating part 48 to the shaft 50 of the prime-mover. It is, of course, preferable to have the press operated by means of a constant speed motor so that the rotation of the cam shaft will be persistently uniform, giving the required time of contact between the ndenting punches. In this lever type of sealing press, it has proved of decided advantage to actuate the lever by means of a cam even with manual operation. The reason for this advantage is that the lever 41 must be swung around at least and back again for each seal, which consumes ordinarily a satisfactory length of time for producing the proper seal. It also positively prevents the hammer blow effect b ecause of the very gradual closing and opening of the lever supporting the ndenting punch.

I do not intend to be limited save as the scope of the prior art and ofthe attached claims may require.

I claim:

1. In a tube sealing press, the combination comprising, a pair of ndenting punches movable relative to each other, operating means for movingsaid punches relative to each other, electric heaters arranged so as to heat said punches and being located within and electrically insulated d from said punches, heat responsive means located adjacent one of said punches so as to be responsive to the heat of said punch, heat control means connected to said one of said heaters to control the heat of said heater and connected to said heat responsive means so as to be controlled by said heat responsive means, and an adjustable cam operatively interposed between said punches and said means so as to limit the movement of said punches relative to each other.

2. In a tube sealing press, the combination comprising, a pair of ndenting punches movable relative to each other, operating means for moving said punches relative to each other, electric heaters arranged so as to heat said punches and being located within and electrically insulated from said punches, heat responsive means located adjacent one of said punches so as to be responsive to the heat of said punch, heat control means connected to said one of said heaters to control the heat of said heater and connected to said heat responsive means so as to be controlled by said heat responsive means, a shaft forming a part of said operating means, a central eccentric fastened to said shaft, and an outer cam adjustably secured to said eccentric so that the eccentricity of said outer cam relative to said shaft is adjustable.

3. In a tube sealing press, the combination comprising, a pair of ndenting punches movable relative to each other, operating means for moving said punches relative to each other, electric heaters arranged so as to heat said punches and being located within and electrically insulated from said punches, heat responsive means located adjacent one of said punches so as to be responsive to the heat of said punch, heat control means connected to said one of said heaters to control the heat of said heater and connected to said heat responsive means so as to be controlled by said heat responsive means, a shaft forming a part of said operating means, a central eccentric fastened to said shaft, an outer cam adjustably secured to said eccentric, and indicia oppositely disposed on said eccentric and on said outer cam so that the eccentricity of said cam relative to said shaft is adjustable by minute variations.

4. Ina tube sealing press, the combination comprising, a pair of ndenting punches'movable relative to each other, operating means for movu' ling said punches relative to each other, electric heaters arranged so as to heat said punches and being located within and electrically insulated from said punches, heat responsive means located adjacent one of said punches so as to be responsive to the heat of said punch, heat control means connected to said one of said heaters to control the heat of said heater and connected to said heat, responsive means so as to be controlled by said heat responsive means, electrically operated indicating means connected in the circuit of said heaters so as to indicate when heat is applied to said heaters, and an adjustable 'cam operatively interposed between said punches and said means so as to limit the movement of said punches rela'- tive to each other.

5. In a tube sealing press, the combination comprising, a pair o indenting punches movable `cated adjacent one of relative to each other, operating means for moving said punches relative to each other, electric heaters arranged so as to heat said punches and being located within and electrically insulated from said punches, heat responsive means losaid punches so as to be responsive to the heat of said punch, heat control means connected to said one of said heaters to control the heat of said heater and connected to said heat responsive means so as to be controlled by said heat responsive means, electrically operated indicating means connected in the circuit of said heaters so as to indicate when heat is applied to said heaters, a shaft forming a part of said operating means, a central eccentric fastened to said shaft, and an outer cam adjustably secured to said eccentric so that the eccentricity of said outer cam relative to said shaft is adjustable.

6.` In a tube sealing press, the combination comprising, a pair of indenting punches movable relative to eachother, operative means for moving said punches relative to each other, electric heaters arranged so as to heat said punches and being located within and electrically insulated from said punches, heat responsive means located adjacent one of said punches so as to be responsive to the heat of said punch, heat control means connected to said oneof said heaters to control the heat of said heater and connected to said heat responsive means so as to be controlled by said heat responsive means, electrically operated indicating means connected in the circuit of said heaters so as to indicate when heat is applied to said heaters, a shaft forming a part of said operating means, a central eccentric fastened to said shaft, an outer cam adjustably secured to said eccentric, and indicia oppositely disposed on said eccentric and on said outer cam so that the eccentricity of said -cam relative to said shaft is adjustable by,minute variations.

7. A press suitable for use in sealing collapsible tubes having a coating of thermo-plastic cement which require an accurate adjustment of pressure and heat, said press comprising, a pair of indenting punches mounted for movement relative to each other, operating means for moving said punches relative to each other, mechanical meansinterposed between said operating means and said punches for accurately adjusting the relative movement of said punches vcaused by said operating means, heating means located in each of said jaws and arranged to apply heat to said jaws and to the portion of the tube between said jaws and electrically insulated from said jaws, and heat-responsive means located in at least one of said jaws so as to be res nsive to the heat of said jaw and connected to control the supply of heat to said heating means. t

8. A press suitable for use in sealing collapsible tubes having a coating of thermo-plastic cement which require an accurate adjustment of pressure and heat, said press comprising, a pair of indenting punches mounted for movement relative to ,each other, a lever pivotally mounted for rotation about a fixed point and supporting one of said punches, operating means for moving said punches relative to each other, an adjustable cam interposed between said operating means and said lever for accurately controlling the relative movement of said punches caused by said voperating means, a spring stressing said lever against said cam and consequently stressing said punches away from each other, heating means located in each of said jaws and arranged to apply heat to said jaws and to a portion of the tube between said jaws and electrically insulated from said jaws, heat-responsive means located in at least one of said jaws so as to be responsive to the heat of said jaw, and an electric switch connected between the heating means in said jaw or jaws in which said heat-responsive means is located and controlled by said heat-responsive means to control the supply of electricity to said heating means.

(JHARLES J. WESTIN. 

